This PDF file contains the front matter associated with SPIE Proceedings Volume 8487, including the Title Page, Copyright information, Table of Contents, and Conference Committee listing.

Measurement of the concentration and size of suspended aerosol particles can be useful for a variety of applications. Scanning nephelometers are frequently employed in such measurement; however, their methodology requires long measurement times and places limitations on scattering angle. We have developed a non-scanning laser polar nephelometer that allows for near-instantaneous measurement and greater angular range. This instrument uses both refractive and reflective components to image light scattered from a volume of scattering particles onto an imaging sensor, while allowing for introduction of a polarization analyzer. The scattering volume itself is imaged in the center of the sensor, whereas the light scattered at various angles is imaged about the sensor. Angles from one hemisphere are imaged, with an angular resolution of better than one degree. Preliminary data from suspended water droplets match closely those quoted in the literature, with data collected from angles closer to forward- and back-scattered angles. Design requirements; the optical design and implementation; and preliminary data and analysis are presented.

The Bragg Reflection Polarimeter (BRP) on the NASA Gravity and Extreme Magnetism Small Explorer Mission is designed to measure the linear polarization of astrophysical sources in a narrow band centered at about 500 eV. X-rays are focused by Wolter I mirrors through a 4.5 m focal length to a time projection chamber (TPC) polarimeter, sensitive between 2{10 keV. In this optical path lies the BRP multilayer reflector at a nominal 45 degree incidence angle. The reflector reflects soft X-rays to the BRP detector and transmits hard X-rays to the TPC. As the spacecraft rotates about the optical axis, the reflected count rate will vary depending on the polarization of the incident beam. However, false polarization signals may be produced due to misalignments and spacecraft pointing wobble. Monte-Carlo simulations have been carried out, showing that the false modulation is below the statistical uncertainties for the expected focal plane offsets of <~ 2 mm.

Liquid lenses based on the principle of driving two dielectric fluids via controlled electric field were investigated with an experimental apparatus designed for analysis of wave front read from a Shack-Hartmann sensor. Due to small available aperture and requirements in dynamic responses, wave front measurement was selected for study of optical characteristics in dielectric lenses. With the advent of commercial electro-optics sensors in wave front measurement, the experimental apparatus was first designed and simulated with the help of ASAP program. The simulated results proved the conceptual design with handful of engineering insights so that less trial and error efforts could be relieved from building the optics system on the bench. In-house built liquid lens modules with driving circuits were then set on the apparatus for initial calibration and functional tests. Since the electric field generated for the control of liquid profile must be alternating current, various frequency and modulation schemes were put through the liquid lens module to further study the influences on dynamic responses in terms of optical characteristics. Furthermore, effects due to material impurity and ambient effects were also carefully studied for established the fundamental phenomena of liquid lenses made of dielectric fluids. More detailed observations were possible with the measured wave-front data. In conclusion, the wave-front measurement proved to be more reliable and less expensive compared to measurement based on interferometer.

This study proposes an innovative optical mechanism with a miniature motorized circular wheel for polarization optics for an ultra-broadband polarization state generator. The proposed apparatus can be suitable for a polarimetric microspectrophotometer for measurements of micro optics and metamaterials with circular dichroism and linear dichroism. Different types of micro optics have their own wavelength dependence, meaning different curves in the broadband range of light. This study presents an ultra-broadband platform for measuring and identifying micro optics such as chiral metamaterials, plasmonics, micro polarizers, and patterned retarders. The key component of a polarimetric microspectrophotometer is a polarization state generator (PSG). A simple PSG consists of a polarizer and a waveplate. An arbitrary polarization state can be created by rotating either the polarizer or the waveplate. Sheet polarizers and achromatic waveplates have a limited bandwidth range. For the ultra-broadband measurement range of 400 nm to 1700 nm, the PSG needs at least three sheet polarizers and three achromatic waveplates: 400 nm-700 nm, 700 nm-1000 nm, and 1000 nm-1700 nm. This optical mechanism, which consists of only one control motor and two high precision unidirectional bearings, includes several polarizers and waveplates arranged in a matrix on a circular wheel. This apparatus can shift one of the polarizers and waveplates to a predetermined position and rotate all the polarizers to change the polarization status. An ultra-broadband polarimetric microspectrophotometer with a compact motorized wheel is an advanced polarization optical instrument for research on chiral metamaterials, plasmonics, micro polarization optics, green optics, and bio optics.

Small and compact optical system designs are needed in nearly all application scenarios of optical projection and imaging systems, e.g. automotive, metrology, medical or multimedia. Most active optical systems are based on separated imaging (e.g. camera unit) and image generating units (e.g. projection unit). This fact limits the geometrical miniaturization of the system. We present compact optical system designs using the new technology of bi-directional sensor devices. These devices combine light emitting and light detecting elements on one single chip. The application of such innovative opto-electronic devices - so-called bi-directional OLED microdisplays (BiMiDs) - offer a huge potential for miniaturization with a simultaneous increase of performance due to a new integration step. For these new bi-directional sensor devices new optical design concepts for simultaneous and sequential emission and detection are necessary. Because the simultaneous emission and detection can disturb the functionality of the optical system. New concepts has to be applied. A first concept is an exemplary 3-D metrology system applying fringe projection. A second concept is a pico-projection system with an integrated camera function. For both concepts the system configurations and the optical design are discussed. Due to the application of the bi-directional sensor device ultra-compact systems are presented.

An illumination system for a microdisplay projector with a two-step imaging system is described here. In the first step, an imaging condenser creates an image of the LED at the color combiner entrance window. In the second step, we relay the image of the integrator exit window onto the micro-display. The illuminator demonstrates high collection efficiency, small footprint, and efficient mixing of light from RGB LEDs that provides required uniformity. A variety of approaches to collecting light emitted from LEDs of various types are compared, leading to the two-step design. A design example using a 0.55” diagonal DLP-based optical engine is presented with the following characteristics: Footprint: 3.9”x3.3”x2.0” (25.7 cubic inches) Light output: 338 white lumens Efficiency: 4.7 lm/watt

A full HD projection system which has single mechanics produces 8-view stereoscopic image. This system combines temporal and spatial multiplex. Base on the DMD fast switching speed, multiple image are produced. The different images are generated by specific DMD and specific synchronized LED. This means temporal multiplex which is related to the signal driving. On the diffuser, it is equivalent eight times HD resolution in horizontal. Therefore, spatial multiplex stripe image is on the screen.

We have developed the geometrical stereo matching image guidance for ground vehicle on focused image pixel grouping and stacked images statistical operation. The two imagers are mounted on the 5 degrees of freedom gimbal unit. The gimbal unit gives each imager the independent yaw and pitch movement, and makes the same rigid yaw rotation on the two imagers. The fast focus image is derived from the calculating the developed wavelet focus measure value of the horizontal high pass image and the vertical high pass image of the Daubechies wavelet transformed image. The highest wavelet focus measure value among them gives the best focus image directly. This focusing operation works finely similar to the other differential image techniques. We used the stereo matching operation between the binary blocked high pass images corresponding to the best focus image. To construct the binary blocked high pass image, we apply the 8 directional adjacent pixel connection to the binary high pass image. The group of the main block elements of the binary image can work as the appropriate matching block. The wide image and narrow image stereo matching operation on the binary high pass image give the correct matching. In particular the narrow image stereo matching operation provides the common area of the right image and the left image. For finding the surface we used the brightness variation of each pixel point through the stacked images for the focusing operation. The kinds of the calculated brightness variations are the standard variation and the absolute deviation from the average brightness on each pixel point. We applied the threshold to the variation and deviation to classify the image area into the mild variation brightness surface area and rough variation brightness surface area. The rough variation brightness surface area covers the group of the main blocked elements in the binary image.

MacAdam ellipses and the 1976 u'v' chromaticity space are commonly used in the illumination and LED industries. Delta E 2000 (ΔE) is the most up-to-date color difference metric endorsed by CIE and is more reliable than earlier metrics. This paper shows how the ΔE 2000 standard can be used to derive ellipses to be plotted in the well-known 1931 xy color space and examines the validity of MacAdam ellipses and the 1976 u'v' chromaticity space in terms of this metric. The 1976 u'v' chromaticity space is found, in quantitative terms, to be less uniform than the 1931 xy chromaticity space based on ΔE 2000. This paper recommends ΔE calculations as a quantitative tool, the proposed ellipses as a descriptive tool, and the total abandonment of the 1976 u'v' color space.

The use of aspheres has become common in minimizing aberrations, reducing weight and the overall package. With new technology for fabrication and metrology being introduced, aspheres have experienced increasing use in wide applications. Although new techniques allow for tighter tolerance and steeper geometries, there still remains a significant challenge in designing aspheres for manufacturability and testing. While the topic of designing for fabrication and metrology limitations has been highlighted over the years, the design process continues to be complex and may prevent the optical designer from reaching an optimum solution that meets both optical performance and manufacturing capabilities. In achieving such goals, it is important to not only have a fundamental understanding of aspheres and its uses, but also the flow for a design process using such elements. Without adding the correct constraints and varying them at the correct time, the design may take extreme forms and hence eliminate fabrication options. In this paper, we present a method for optimizing aspheres which can be applied to designing simple on-axis single elements all the way to high numerical aperture multi-element systems. It will outline the procedure of the necessary steps, configurations to pay attention to, and potential courses of action in order to design for the appropriate solution. Understanding these issues will enable the optical designer to efficiently produce an asphere meeting optical requirements and fabrication capabilities.

This paper describes a process for designing a radially-symmetric lens that receives light from a uniform, Lambertian disk of finite size and produces a prescribed intensity distribution. An algorithm is presented to design such a lens based on input parameters including the source diameter and luminance, the vertex location and center thickness of the lens, the desired output intensity distribution, and the output beam angle. The design process involves starting with a small center portion of the lens and progressively adding discrete, continuous sections around its diameter. Each section is tailored to produce the desired intensity in the output beam based on the projected area of the source in the far field according to the principle of luminance engineering.

We describe a method approaching direct optimization of the rms wavefront error of a lens including tolerances. By including the effect of tolerances in the error function, the designer can choose to improve the as-built performance with a fixed set of tolerances and/or reduce the cost of production lenses with looser tolerances. The method relies on the speed of differential tolerance analysis and has recently become practical due to the combination of continuing increases in computer hardware speed and multiple core processing We illustrate the method’s use on a Cooke triplet, a double Gauss, and two plastic mobile phone camera lenses.

Merit function with higher efficiency is helpful for lens design, especially in hybrid imaging system. Although different merit functions have been proposed in recent years, for example, Fisher information, Hilbert space angle, mean square error (MSE) based on optical transfer function, intermediate or restored image, structure similarity, correlation or statistical properties from point spread function (PSF). But it is still an unanswered question that which merit function is best for optimization in hybrid imaging system. So, a novel approach which is based on finite impulse response of hybrid imaging system is proposed. And several merit functions, blur MSE, PSF similarity, modulation transfer function (MTF) area and volume are evaluated by present method. The results show that performance of merit function is not only affected by noise, sampling ratio. But the effect of restoration filter should be also considered. Finally, compare with PSF similarity, blur MTF in area and volume; blur MSE provide much stable results in hybrid imaging system, which means it could be an optimized merit function in hybrid imaging system.

SAGUARO is open-source software developed to simplify data assimilation, analysis, and visualization by providing a single framework for disparate data sources from raw hardware measurements to optical simulation output. Developed with a user-friendly graphical interface in the MATLAB^TM environment, SAGUARO is intended to be easy for the enduser in search of useful optical information as well as the developer wanting to add new modules and functionalities. We present here the flexibility of the SAGUARO software and discuss how it can be applied to the wider optical engineering community.

Capturing light field data with a plenoptic camera has been discussed extensively in the literature. However, recent improvements in digital imaging have made demonstration and commercialization of plenoptic cameras feasible. The raw images obtained with plenoptic cameras consist of an array of small circular images, each of which capture local spatial and trajectory information regarding the light rays incident on that point. Here, we seek to develop techniques for representing such images with a natural set of basis functions. In doing so, reconstruction of slices through the light field data, as well as image compression can be easily achieved.

LED flash module becomes popular in current mobile communication devices, such as for the smart phones and tablet. As a lighting apparatus for image taking, photo rendering performance is crucial. We explore the LED flash lens design with a stress of photorealistic rendering application toward a high-performance LED flash illumination.

The current paper deals with the design of macro imaging optics with x-y-ratios significantly differing from unity. Such optics might be based on combinations of cylindrical lenses. Description and design procedures use the paraxial method. Special attention is drawn to questions of aperture stop design and some Fourier optical consequences. A next step would be consideration of tilted object planes and the satisfaction of the Scheimpflug rule, which finally leads to a simple realization. The paper can be seen as a follow up to last year’s papers on Fourier optics vs. the Scheimpflug principle and multiple reflections in lenses.

The resolution of conventional space telescopes is determined by the size of their primary mirror. However, quality high resolution images can be obtained using inexpensive micro-satellite carrying an optical synthetic aperture telescope. Noise, quantization (A to D) errors and aberrations due to imprecise location and/or deformation of optical parts may all degrade the accuracy of the raw, unprocessed, individual images and thus also the quality and resolution of the final synthesized image. These are analyzed in this paper. Sample simulated images are presented, as well as some design and processing rules for such systems.

Using biometric signatures for identity recognition has been practiced for centuries. Recently, iris recognition system attracts much attention due to its high accuracy and high stability. The texture feature of iris provides a signature that is unique for each subject. Currently most commercial iris recognition systems acquire images in less than 50 cm, which is a serious constraint that needs to be broken if we want to use it for airport access or entrance that requires high turn-over rate . In order to capture the iris patterns from a distance, in this study, we developed a telephoto imaging system with image processing techniques. By using the cubic phase mask positioned front of the camera, the point spread function was kept constant over a wide range of defocus. With adequate decoding filter, the blurred image was restored, where the working distance between the subject and the camera can be achieved over 3m associated with 500mm focal length and aperture F/6.3. The simulation and experimental results validated the proposed scheme, where the depth of focus of iris camera was triply extended over the traditional optics, while keeping sufficient recognition accuracy.

In order to validate and to optimize the imaging capabilities of a micro-lens-array (MLA) based optical detector dedicated for preclinical in-vivo small animal imaging applications a numeric investigation framework is developed. The framework is laid-out to study the following MLA detector parameters: micro-lens diameter (D) and focal length (f), as well as sensor pixel size (A). Two mathematical models are implemented for light modeling: line-based and cone-based ray projections. Since the MLA detector requires mathematical postprocessing, specifically inverse mapping for image formation, the framework is fully integrated into such approach. MLA detector designs have been studied within valid parameter ranges yielding sub-millimeter spatial resolution for in vivo imaging of mice for detector-object-distances (t) up to 50 mm. In summary, there is a non-linear dependency of the detector's spatial resolution, scaling with D and f, for any respective t. On the other hand, detector efficiency is strongly dependent on f. Regardless of mathematical postprocessing the following set of intrinsic detector parameters had been found optimal for the intended application: D = 0.336 mm, f = 4.0 mm, A = 0.048 mm. When mathematical postprocessing is involved, particularly three-dimensional surface recognition, increasing f (cf. decreasing D) yields solid angles of the incoming rays closer to 90° and, thus, will decrease spatial depth information from the elementary images. Hence, a setup with D not larger than 0.5 mm and f between 2.0 mm and 3.0 mm is recommended.

In the area of bioelectromagnetic studies there is a growing interest to understand the mechanisms leading to nanosecond electric fields induced electroporation. Real-time imaging techniques at molecular level could probably bring further advances on how electric fields interact with living cells. However the investigations are limited by the present-day lack of these kinds of advanced instrumentations. In this context, we present an innovative electro-optical pump-probe system. The aim of our project is to provide a performing and compact device for electrical stimulation and multiplex Coherent anti-Stokes Raman Scattering (M-CARS) imaging of biological cells at once. The system consists of a 1064 nm sub-nanosecond laser source providing both a monochromatic pump and a polychromatic Stokes optical beam used in a CARS process, as well as the trigger beam for the optoelectronic switching-based electrical pulse generator. The polychromatic Stokes beam (from 600 to 1700 nm) results from a supercontinuum generation in a photonic crystal fiber (PCF). A detailed spectro-temporal characterization of such a broadband spectrum shows the impact of the nonlinear propagation in the fiber on the Stokes wave. Despite the temporal distortions observable on Stokes pulse profiles, their spectral synchronization with the pump pulse remains possible and efficient in the interesting region between 1100 nm and 1700 nm. The electrical stimulation device consists of a customized generator combining microstrip-line technology and laser-triggered photoconductive semiconductor switches. Our experimental characterization highlights the capability for such a generator to control the main pulse parameters (profile, amplitude and duration) and to be easily synchronized with the imaging system. We finally test and calibrate the system by means of a KDP crystal. The preliminary results suggest that this electro-optical system provides a suitable tool for real-time investigation of bioelectromagnetic interactions in the nanosecond and sub-nanosecond regime.

Although confocal fluorescence laser scanning microscopy is a widely used technique in biology, these microscopes are at present uncommon in medical diagnostics. However laser scanning fluorescence microscopy is a non-invasive imaging technique that allows depth resolved investigations of skin disorders. High costs and large outline are factors which impede the establishment of this technology in medical practice. To overcome this obstacle, we have designed a portable confocal laser scanning fluorescence microscope and realized an optical demonstration set-up, offering a field of view of 500μm x 500μm. The microscope is based on a dual axis MEMS mirror where the confocal character of the system resides in the use of the same path for illumination and detection with the rejection of out-of-focus light by a pinhole. Illumination is provided by a laser and the fluorescence light is separated from the illumination light by a filter, before being detected. The ability to perform cross-sectional imaging of fluorescence specimen will be given by an integrated z-shifter.

This study introduces a multimode compatible forward scanning optical probe which includes tunable iris and varifocal lens based on micro-electro-fluidics. Concept development and optical design is carried out for the optical probe. The result shows that it can be adaptively used as a multimodal imaging tool for both optical coherence tomography and microscopy. It also has been proved that an optical depth scanning with the designed probe can provide optical coherence tomography with high resolution without any mechanical movement of the optics.

The use of Adaptive Optics (AO) in ophthalmologic instruments to image human retinas has been probed to improve the imaging lateral resolution, by correcting both static and dynamic aberrations inherent in human eyes. Typically, the configuration of the AO arm uses an infrared beam from a superluminescent diode (SLD), which is focused on the retina, acting as a point source. The back reflected light emerges through the eye optical system bringing with it the aberrations of the cornea. The aberrated wavefront is measured with a Shack – Hartmann wavefront sensor (SHWFS). However, the aberrations in the optical imaging system can reduced the performance of the wave front correction. The aim of this work is to present an optimized first stage AO experimental setup for in vivo retinal imaging. In our proposal, the imaging optical system has been designed in order to reduce spherical aberrations due to the lenses. The ANSI Standard is followed assuring the safety power levels. The performance of the system will be compared with a commercial aberrometer. This system will be used as the AO arm of a flood-illuminated fundus camera system for retinal imaging. We present preliminary experimental results showing the enhancement.

While the use of optics in the playback of music has been a tremendously successful technology and laser light shows are a common occurrence, other intersections of optics and music tend to be less well known. Topics such as optics-based instruments, performance tools and effects, instrument characterization and manufacturing, recording, playback, and signal processing are explored.

A short paper covering optics and music: the Uni-Vibe, which is responsible for the unique sound of Hendrix’ Woodstock performance, is one of many phasing devices based on photo conductive cells used as variable resistors. However, its sound is well distinguishable from other phasers. In the paper we shall discuss the basic properties and try to qualify and quantify the effect on the spectra of certain chords. The present paper is a side effect of the musical interests of the authors and is triggered by the announcement of the Novel Systems Session including the topics ’Optics and Music’ and Historical Devices.

Uranium compounds have been used to give glass a fluorescent shining green color for hundreds of years. Such glass has been found in daily use articles as well as in optical filters. We have come across its interesting properties looking for a nearly first order volume scatterer, which, after initial reflection, does not provide significant multiple scatter. The basic idea was to excite a fluorescent material under geometrically well defined conditions and use the pattern of the emitted light as a model for volume scatter. Although it is obvious that the basic mechanism is different from scatter, the obtained pattern is useful for device calibration and investigations on imaging devices for semitransparent scattering or self emitting materials. In the current paper some mostly experimental investigations on a variety of uranium glass are presented, questions of its usability as a volume scatter and emission standard are discussed. With special regards to the conference - a historical review on the topic is given.

The paper overviews various supporting ways for large-size movement mirrors, and the advantages and disadvantages of the support methods are summarized. Some valuable optimization methods to improve support effects are also introduced. As a case study, a radial segment-face contact support method is proposed to solve the support problem for a large-aperture rotating prism, and a two-step optimization method is implemented to improve the support effects. The surface deformations under different support separated angles are evaluated. The overview can be as good references for large-size mirror support design in similar opto-mechanical systems especially under movement conditions.

Data transmission over optical fiber followed by transferring to mm wavelength range using an optical heterodyne is considered. Data signals enter into the optical fiber. Spectrum of the data signals are transmitted in millimeter range by optical heterodyne at the receiver. Millimeter range signals are radiated by antenna systems.

This work presents the possibility of phase tomography of optical-anisotropic multilayered biological structures. The superposition approach of polarization manifestation of optical anisotropy of polycrystalline protein networks is proposed. The optical model of polycrystalline networks of biological tissues protein fibrils is presented. The technique of phase tomography based on determining the coordinate distributions of Mueller-matrix elements of biological tissues is suggested. The results of investigating the interrelation between the values of statistical (statistical moments of the 1^st- 4^th order) parameters are presented. They characterize the coordinate distributions of phase shifts of biological tissue layer of different optical thickness and the degree of muscle dystrophy.

The model of interaction of laser radiation with biological tissue as a two-component amorphous-crystalline matrix was proposed. The processes of formation of polarization of laser radiation are considered, taking into account birefringence network protein fibrils. Measurement of the coordinate distribution of polarization states in the location of the laser micropolarimetr was conducted .The results of investigating the interrelation between the values of correlation (correlation area, asymmetry coefficient and autocorrelation function excess) and fractal (dispersion of logarithmic dependencies of power spectra) parameters are presented. They characterize the coordinate distributions of polarization azimuth of laser images of histological sections of women’s reproductive sphere tissues and pathological changes in human organism. The diagnostic criteria of the prolapse of the vaginal tissue arising are determined.

This paper presents a description of the principles defining period of death by polarimetric study temporal dynamics of changes in optical anisotropy of the cerebrospinal fluid of the human body. The optical model of polycrystalline networks of human body liquor is suggested. The results of investigating the interrelation between the values of statistical (statistical moments of the 1^st-4^th order), correlation (correlation area, asymmetry coefficient and autocorrelation function excess) and fractal (dispersion of logarithmic dependencies of power spectra) parameters are presented. They characterize the coordinate distributions of absolute value and phase of complex degree of mutual polarization in the points of laser images of liquor and temporal dynamics of optical anisotropy of human body liquor. The diagnostic criteria of death coming prescription are determined.

This paper presented data on the method of coherent space-frequency filtering of coordinate distributions azimuth and ellipticity of polarization of the laser plasma image. The optical model of polycrystalline networks of human blood plasma is suggested. The results of investigating the interrelation between the values of blood plasma polarization maps statistical (statistical moments of the 1^st-4^th order) parameters and pathological changes of rectum wall are presented. They characterize the coordinate distributions of the azimuth and ellipticity of Fourier transforms of laser images of human blood plasma. The diagnostic criteria of rectum cancer are determined.